Everyone who plays golf - and apparently there are about 30 million who play at least once a month - knows that the swing is everything. When I was an avid player, I recall turning away from watching someone with a lousy swing for fear I'd pick up bad habits. My favorite time at a golf event was to go to the driving range and watch the professionals swing their clubs.

So it's not surprising, that something like Mobiplex is a very intriguing idea to me - someone's who's spent quite a sum on instructors just to constantly tweak and improve my swing.

Mobiplex is a Santa Clara, Calif.-based startup that just raised $3.1 million to build out hardware for athletes or sports enthusiasts who want to improve their golf swing, and in the future their tennis swing and their baseball pitch.

Given the background of the founder Vijay Nadkarni, Mobiplex probably could have raised money from venture capitalists. In 1998, Nadkarni founded Veraz Networks, which was funded by Norwest Venture Capital and Kleiner Perkins, and eventually IPO'd in 2007. In 2007, he co-founded Wellcore (a monitoring device), which was funded by Menlo Ventures. The company was sold for an undisclosed amount.

But Nadkarni raised the round from 30 investors, who are high networth individuals but not avid angels, said Nadkarni, in an interview with me.

Mobiplex's first product called SwingTip is a golf swing analzyer, which was released in September. The SwingTip, which is essentially a mobile golf swing coach, sells for $129.99 and is available at Amazon, Butler Golf, Dr. Bott, Golf Galaxy, MKRAK Management, PlayBetterGolf.com and SmartHome.com.

The SwingTip, which uses wireless 3D motion sensor, attaches to the golf club and monitors the swing. The data, which is accessible from a smart phone or tablet, includes the club path, club speed, impact zone (where the ball hits the club head) to the rotation of the wrist. SwingTip analyzes hundreds of data from a single swing alone.

Nadkarni says of the 30 million golfers in the US, roughly 10% take lessons. So he's hoping the other 90% who don't spend the money for lessons (since they can be costly), would spend the money for some assistance. He's also betting that golfers will spend the money, since they typically spend a lot on this sport. The market for sports equipment is $5.8 billion, according to Nadkarni.

In the future, Mobiplex plans to expand beyond golf. The next products will target tennis players who want to improve their swing and baseball players who want to improve their pitches.